<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>原型面试题</title>
    <script>
        var A = function(){
       }
        A.prototype.n = 1
        var b = new A()
        A.prototype = {
            n:2,
            m:3
        }
        
        // var c = new A()
        console.log(b.n,A.prototype.n)
        console.log(A._proto_)
    </script>
</head>
<body>
    
</body>
</html>